Let's roll up our sleeves and solve this. We have 250 and we're going to multiply it by 16, essentially adding 250 to itself 16 times.
Step 1: 0 + 250 = 250
Step 2: 250 + 250 = 500
Step 3: 500 + 250 = 750
Step 4: 750 + 250 = 1000
Step 5: 1000 + 250 = 1250
Step 6: 1250 + 250 = 1500
Step 7: 1500 + 250 = 1750
Step 8: 1750 + 250 = 2000
Step 9: 2000 + 250 = 2250
Step 10: 2250 + 250 = 2500
Step 11: 2500 + 250 = 2750
Step 12: 2750 + 250 = 3000
Step 13: 3000 + 250 = 3250
Step 14: 3250 + 250 = 3500
Step 15: 3500 + 250 = 3750
Step 16: 3750 + 250 = 4000

So, 250*16 = 4000